A woman who campaigned tirelessly against guns, knives and gang culture was stabbed to death in a frenzied attack carried out by her grandson.

Pat Regan, who was known nationally for her anti-violence campaign, was killed in her own home by the 21-year-old Rakeem Regan.

Regan, who was said to have worshipped his grandmother, had developed severe psychiatric problems and was suffering from paranoid schizophrenia at the time of the killing.

He denied murdering Mrs Regan at Leeds Crown Court yesterday and the prosecution accepted his plea of guilty to manslaughter on the grounds of diminished responsibility.

The court was told that he had been behaving strangely in the days leading up to the stabbing in June last year and was taken to hospital by his grandmother the night before her death.

Regan was assessed by a mental health nurse, who decided that he needed acute care and offered to admit him for treatment, but Mrs Regan, 53, said that she wanted to look after him at her flat in the centre of Leeds.

She took him home and watched over him during the night as he tried to sleep. Apparently, she told a friend that she felt safe with her grandson and she was certain he would not harm her. When he woke up the next morning, he was in a delusional mental state and became convinced that his grandmother was a paedophile who wanted to abuse him.

He carried out a sustained assault on Mrs Regan, punching her and inflicting multiple stab wounds to her head and neck. Regan left his grandmother lying dead in the flat with part of the broken knife embedded in her left eye, and went to the city’s railway station, where he twice stabbed a member of staff who tried to prevent him from jumping on to the tracks.

He was arrested at the station. Only later was his grandmother’s body discovered by a community psychiatric team who had arranged to visit him at the flat later that afternoon.

Regan also admitted a charge of wounding with intent after his attack on the railway station’s duty manager.

The Recorder of Leeds, Judge Peter Collier, QC, ordered Regan to be detained indefinitely at Rampton secure hospital in Nottinghamshire.

Jeremy Richardson, QC, for the prosecution, described the case as “a tragedy from every viewpoint”.

He said that Mrs Regan had received national acclaim for her campaign against gun and knife crime, which began after her son, Danny, was shot dead in 2002.

As a leading member of Mothers Against Violence, she led street marches, met Cabinet ministers and took her message into dozens of schools and prisons. She had played a key part in her grandson’s upbringing, but his behaviour changed after he was stabbed four months before the killing.

A few days before her death, Regan was arrested after a burglary. He was released without charge, but claimed that the police had raped him and were going to kill him.

Regan’s family members described him as “ranting and raving and utterly incoherent”. He had also claimed that he was being chased by aliens.

The family’s doctor contacted community mental health professionals two days before the stabbing and a series of visits and discussions took place, but Mrs Regan was determined to care for her grandson at home.

The court was told that two consultant psychiatrists who examined Regan after the killing were “in complete agreement” that he was suffering from paranoid schizophrenia.

Graham Hyland, QC, for the defence, said that Mrs Regan was a woman “much loved and respected” not only by her large family but by all who knew her.

“It was Pat Regan’s wish for him to come home \ with medication. Tragically, that wish, born out of her love and concern for her grandson, cost Pat Regan her life the following morning.

“He loved his grandmother and she loved him. Therein lies the enormous human tragedy of this very, very sad case.” The judge said that Mrs Regan’s determination to care for her grandson had been “typical of her indomitable character”.

He agreed that the mental health professionals involved in the case had behaved “entirely properly”, but suggested that, with hindsight, lessons could be learnt for the future.

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